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<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>11CSS文本属性</title>
  <style>
    h1 {
      text-align: center;
    }
  </style>
</head>
<body>


  <h1>居中对齐的标标题</h1>
  
</body>
</html>